P Tau 181, CSF, CLEIA

Phosphorylated Tau 181

7 days

Chemiluminescent enzyme immunoassay (CLEIA)

• A negative CSF p-tau 181 result indicates no biochemical evidence of tau tangle pathology and, when considered with the CSF Amyloid β-42/40 ratio, reduces the likelihood of Alzheimer’s disease (AD).
• A positive CSF p-tau 181 result reflects elevated phosphorylated tau and supports the presence of Alzheimer-related tau pathology. When combined with a positive CSF Amyloid β-42/40 ratio, it contributes to a biomarker profile consistent with biological Alzheimer’s disease.

As with all neurological biomarkers, abnormal results should always be interpreted in the context of the clinical presentation, cognitive assessment, neuroimaging, and complementary CSF biomarkers (e.g., Amyloid-β 42/40 ratio, Total tau etc.), as well as any relevant medical history.

Accredited NRL Laboratory

Weekly

In Alzheimer’s disease (AD), normal tau phosphorylation is disrupted, resulting in tau hyperphosphorylation and the formation of abnormal phosphorylation sites. This assay specifically measures tau phosphorylated at threonine 181 (p-tau181).
Measurement of p-tau181 in CSF is intended to support the evaluation of patients with cognitive impairment who are being assessed for AD and other causes of cognitive decline.
Results should be interpreted as an adjunct to clinical assessment, neuroimaging, and other CSF biomarkers, and do not alone establish a diagnosis.

CSF

0.5 mL

Sarstedt sterile polypropylene tubes

Preferably, the lumbar puncture should be performed in the morning.

Perform the lumbar puncture at the L3/L4 or L4/L5 intervertebral space. Collect the cerebrospinal fluid in an appropriate polypropylene tube and transport it frozen at –20°C.